The British Museum’s new exhibition Vikings: Life and Legend does not subscribe to what curator Gareth Williams calls the “fluffy bunny school of Viking studies”. A generous selection of swords, axes, macho skaldic poetry and battered skulls ensures there’s no danger of the visitor leaving under the misapprehension that the bloodthirsty Norse plunderers of lore were actually a misunderstood bunch of bookish vegetarians with an abhorrence of rapine and pillage.

Yet Iron Maiden fans shouldn’t rejoice just yet. The exhibition – a collaboration with the National Museum of Denmark, from which it arrives, and the National Museums in Berlin, to where it travels next – also seeks to present the Vikings as no more or less violent than the Anglo-Saxons, Franks, Slavs, etc with whom they contended and traded. So alongside the swords and skulls are a wealth of coins, jewellery, combs for grooming lustrous Norse locks and (an implement that should really be mass-produced and sold in the museum shop) a small gold scoop for removing earwax.

Vikings is the first exhibition to be shown in the British Museum’s new Sainsbury Exhibitions Gallery, a subtly lit and functional series of rooms that effectively focus one’s attention on the exhibits. The first you see as you enter is a small brooch decorated with a boat, dating from “between 800 to 1050”. The inexactness turns out to be typical.

The Vikings were a mainly oral culture who left behind few written records. Contemporary accounts of them were written by foreigners, often victims of Viking raids. In the 18th and 19th centuries a cult grew up around them as proud northern warriors, a racial archetype that fed into Nazi fantasies of Aryan dominance. In the face of this mystique, it’s hard say exactly who or what the Vikings actually were. The exhibition’s answer is vague: “Today, the term is used to refer to the many peoples of Scandinavia during the Viking Age (AD800-1050).”

This vagueness spills into the vitrines, which contain no labels, just objects. Blocks of text below the cases explain the contents, though not always precisely. The presence of what appears to be a broken whalebone sword in a vitrine labelled “Women’s accessories from Scandinavia” goes enigmatically unexplained. Similarly a passing mention of women being allowed to inherit property leaves unaddressed wider issues of Viking laws and social structures.

However, the overall narrative is clearly told. It shows how Vikings were raiders and pirates (the original meaning of the word in Old Norse) who were also merchants, travelling as far as Russia and the Byzantine empire in order to trade goods, from whalebone to slaves. Viking settlements appeared throughout northern Europe, a territorial range that under the 11th-century leadership of Cnut the Great (King Canute), took on the lineaments of an empire.

The centrepiece of the exhibition is a longship, housed in a large open room, the curatorial equivalent of the great halls in which the Vikings did their wassailing. The boat was discovered in Roskilde, Denmark, in 1997; its huge size, 37m long, suggests it may have belonged to Cnut. The remnants of its keel and planks are placed in a metal-frame mock-up of the boat. It gives a good impression of how imposing such ships must have looked to nervous monks in soon-to-be-sacked monasteries. A fragment of oral poetry printed on a nearby wall strikes the appropriate chord: “Men will quake with terror/Before the seventy sea-oars/Are given deserved respite/From the labours of the ocean.”

To the non-archaeological eye, the wooden remains of the boat are less impressive than the surrounding mock-up, resembling as they do several large pieces of driftwood. Similarly, the numerous ornaments – gold rings, silver bracelets, necklaces made from jet and glass bead: Vikings loved their bling – are also strikingly crude, paling next to the Frankish and Anglo-Saxon jewellery usefully also on display as comparisons.

The fascination resides not in the artistry of the artefacts but in the way of life that they illustrate. A silver drinking vessel probably looted from a monastery is set next to an Old Norse anti-binge-drinking campaign: “A man shouldn’t clutch at his cup, but moderately drink his mead.” There are toy boats that Viking children played with, and the jawbone of a young Viking warrior, its front teeth filed down to scare opponents. The few snatches of runic writings are comically basic, insights into primitive preoccupations of acquisition and ownership: “Maelbrigda owns this brooch”, “Visgeirr took this plot [of land]”.

It ends with the most sophisticated works on display, a magnificent 12th-century set of chess pieces from the Isle of Lewis and a copper alloy Danish crucifix from the same period, symbol of the spread of Christianity throughout Scandinavia. Then you exit, to find yourself in a room of ancient Egyptian sculpture that would have left the average Viking dumbstruck.